There is known a medical energy irradiation apparatus which inserts an inserting portion thereof shaped like a longer measure into a living body by using a body cavity or performing small incision, and irradiates the tissue of a living body including a lesion with energy, such as laser light, a microwave, radio frequency, and ultrasonic wave, from this inserting portion, thereby destroying the tissue of the lesion by degeneration, necrosis, coagulation, ablation or vaporization.
The medical energy irradiation apparatus is generally for performing a cure by applying direct irradiation with energy to a lesion located on a surface of a tissue of a living body or in the proximity thereof. However, it is also applied to heat-curing for a lesion located in a deep part of a tissue of a living body, such as a prostate gland. Also, there is known a medical energy irradiation apparatus that is configured to be cooled with coolant in the proximity of its energy emitting portion provided in the inserting portion. According to this energy irradiation apparatus, because a tissue of a living body making contact with the energy emitting portion or the neighborhood thereof is cooled in the surface or in the proximity thereof, these parts can be protected from heat-injury and only a deep part of the tissue of a living body can be heated intensively.
When, for example, a cure for a prostate gland is performed by using this medical energy irradiation apparatus, generally the following procedures are performed. That is, the doctors performing a cure for a prostate gland first insert the inserting portion of the medical energy irradiation apparatus toward the urinary bladder from the urethra of patients, and make the emitting portion reach to a portion of the urethra enclosed by the prostate gland (prostatic urethra). Then, in that position, the doctors align the position of the emitting portion to the direction of a target site in the urethra, thus performing irradiation with energy. The doctors generally perform this series of operations while they are observing the views of each position in the urethra by an endoscope that can be inserted in the longitudinal direction.
To describe one example of the above described alignment of the emitting portion in detail, the doctors first insert a predetermined length of the inserting portion of the medical energy irradiation apparatus from the urethra entrance of the patients, and fix the inserting section and the endoscope at this position, and then observe and store the view of the proximal end portion of the urethra irradiated with energy observed by the endoscope in memory. Next, the doctors further insert the endoscope toward a deeper part in the direction of the urinary bladder of the patients by a predetermined length with the inserting section fixed in the urethra, and fix the endoscope at the position, and then again observe and store the view of the distal end portion of the urethra irradiated with energy therein observed by the endoscope in memory.
The doctors repeatedly carry out the above described operations of the endoscope while changing the position of the inserting section to be fixed in the urethra, thereby positioning the emitting portion toward a target position, that is, a target position for irradiating a target site with energy. Also, when the doctors judge that the endoscope has been inserted beyond the target position, they return the inserting section toward the urethra entrance and fix it, and the doctors repeatedly carry out the series of operations of the endoscope, as well, to move the inserting section to the target position, and fix if therein. Further, the doctors have determined a position for fixing the point of the inserting section based on a distance from the seminal colliculus in the urethra to be observed by an endoscope.
Also, when the doctors perform the heat-curing using the medical energy irradiation apparatus described above at a plurality of positions, they repeatedly perform the above described operations for each of the positions.
However, according to the above described method, the doctors determine an irradiation target position for heat-curing by visual observation while they are moving the endoscope. For this reason, although the doctors can roughly grasp the target position, it has been impossible to determine reliably and accurately the portion for fixing the inserting section thereto.
Also, in performing heat-curing by the medical energy irradiation apparatus described above, when the doctors place the emitting portion at an appropriate irradiation target position in a urethra surrounded by a prostate gland, they have sometimes placed the emitting portion at a position closer to the urinary bladder beyond the appropriate irradiation target position in the urethra, or sometimes placed it on the side of external urethral sphincter located at the front of the appropriate irradiation target position in the urethra.
In this way, when the doctors fail to place the inserting portion of the medical energy irradiation apparatus on an appropriate position of placement, the patients cannot obtain a sufficient heat cure effect or can be damaged in the healthy urinary bladder or external urethral sphincter thereof.
Also, when the heat-curing by the medical energy irradiation apparatus described above is performed a plurality of times, the possibility of error operations as described above further increase, because the doctors must perform the operation of positioning the inserting portion a plurality of times.
Also, when the heat-curing is performed by using a medical energy irradiation apparatus provided with an emitting portion having a wide range of energy irradiation, it is difficult for the doctors to limit the range of energy irradiation only to the prostate gland of the irradiation target site. For this reason, the doctors must irradiate accurately the central portion of the prostate gland with energy, but the conventional methods of setting an energy irradiation target position rely on the guesswork of the doctors in some part. Therefore, it has been impossible to avoid errors occurring in determination of an irradiation target position. For this reason, because of deviation from an energy irradiation target position, there have been fears that the patients cannot obtain a sufficient effect of curing or can be damaged in the healthy urinary bladder or external urethral sphincter.
Furthermore, if the patients feel physical disorder caused by the insertion of the inserting portion into them during heat-curing, searing heat due to heat-curing, and pains, and they move by a reflex action, and even though the doctor realize a deviation in the position of placement, the doctors cannot return the inserting portion to the position of placement prior to the position deviation. As a result, there have been fears that the patients cannot obtain a sufficient effect of curing or can be damaged in the healthy urinary bladder or external urethral sphincter.